Wouldn't production be a better measure of economic health than demand?
As it turns out, and this becomes clear if one ponders it awhile and with some nominal competence, "economic health" is an almost meaningless term. Why? Because predication turns on a set of presuppositions the range of values and perspectives of which are so broad, potentially so non-objective, and therefore so arbitrary that there becomes little hope of settling on an agreed definition between a small handful of individuals, much less a statistically valid human population.
For example, some may say that demand indeed is the prime indicator of economic health. Of those, some will say that demand for basics is what counts. Those would be the people for whom life is a grey and sullen affair to be endured from cradle to grave. In other words, the socialist/communist/collectivist praisers of authoritarian rule by which equal poverty is imposed upon one and all and every many is forced to live his life as if it were an apology to his fellow men and the universe for having been born.
At the other extreme would be those who say demand for the most inane triviality is the proper indicator. Those would be the people who see economic health as residing at its apex in endless, mindless, pointless consumerism. Life is a spend-fest wherein the moral man "does his part" by investing in endless procurement, consumption, and waste as he feigns his joyful bouncing from one purchase to the next. He may seem happy, but below the superficiality of his vacuous, plastered-on smile, his life is disturbingly similar in fundamental flavor to the metallic, leaden taste of the toxic and mere existence of his collectivist buddy next door.
The litany of possible choices laying between these extremes is probably large enough to be worthy of note and that covers only one point of view on that particular approach to defining "economic health". There are no doubt a large number of differing demand-centered possibilities that could be asserted as the "correct" measures. There is nothing objectively compelling in any of them insofar as one's assertion of their primacy as the most perfect measure. It's all matters of chocolate v. vanilla. All mere personal opinion.
Some might disagree and say, as you have suggested, that the measure lies in production. Similar sets of manifold points of view may be formulated into theories claiming to be ascendant above all others and they may many of them be perfectly correct of one accepts the entire body of ufundamental presuppositions that underpin them. It is, of course, that last bit which serves as the fly in the ointment. Much as with anuses, most people have opinions. This one want that and that one wants this and people are endlessly driven, it seems, to justify why things should be their way and not another.
I think "economic health" is a baloney term - a political term - contrived and used as a crude but effective bludgeon to affect public opinion. It seems to me to speak very strongly to the sense of entitlement that rages wildly in so many people. The only real difference between individuals lies in which end of the entitlement spectrum they fall. The near-suicidal, auto-apologizing socialist, full of self-absorption in his endless loathing of all things human - himself the apex object of his sadly bitter hatred - sees everyone as entitled to the third party provision of food, shelter, clothing, and so forth. On the other hand we have the equally bankrupt bouncer of Brave New World who expects to have her birth control magically provided by unnamed third party sources... and a nice large screen LED TV... and the great litany of shiny things that makes her go "Ooooooo... I WANT that."
Those who seek power choose their sides, identify the "core issues" (read "the litany of demands") and pander pusuant thereto. Given the ways in which "economics" has been conceptually mangled for the purposes of such pandering, it becomes clear that there is nothing scientifically neutral about the political term and its derivatives such as "economic health". It is pure baloney contrived with the sole purpose of inflaming the base proclivities of avarice and fear. Because it speaks to so fundamental a set of human drives and relies upon the most reliably deplorable qualities of the human spirit, the method works like a charm from generation to generation, and better with each successive iteration precisely due to those rueful characteristics of statistical humanity.
What is not addressed very often in discussions of "economic health", in case you have not noticed, are the notions that are central to human freedom, which itself is the very fountainhead of prosperity and there is a very good reason for this. It appears to me that most people fail to grasp a very fundamental notion regarding statistically significant populations: their statistical nature. This is especially true in the discussion of economies and their "health", particularly by the authoritarian collectivists, but also, if less egregiously, by those of other stripes. The authoritarian collectivist openly, knowingly, and deliberately ignores the statistical nature of large human populations. They think they can force outcomes upon every last individual, thereby fulfilling their personal ambitions in accord with their private definitions of the perfect society. This, of course, is demented in a very real and, as it has turned out, dangerous way as witnessed by the ultimate results this mental orientation has produced in the twentieth century with the slaughter of some 200 millions of presumably innocent people who had the shit protected and served out of them by raging psychopaths such as Mao and Stalin.
They blindly and intransigently press the shoulders of their victim populations into the grindstone that resolutely ignores the statistical and utterly unavoidable truth about such populations: one size does not fit all in the vast and overwhelming majority of human concerns. In economic terms this means that not everyone is going to be prosperous for a given, one-size-fits-all definition of the term. Not all will "make it". Some will be poor. Some will even die. This reality does
not imply in any manner or measure that prosperity is not "ours"; that the land and people are not flourishing. Such notions, when applied statistically to large (i.e. valid) populations must perforce be
taken statistically, which is to say that there will invariably be a
distribution of outcomes. When a land is "prosperous" that distribution appears normal and perhaps toward being tight with a narrow standard deviation. As general prosperity diminishes, the curve widens, skews ever more heavily to "poor", often tightens toward the wealthy (though not always), and sigma is large, meaning simply that more and more people fall to poverty, for a given definition of the term.
This quality of "prosperity" when used as a political term, which is by necessity statistical in nature, cannot be avoided, yet the authoritarian collectivist makes endless believe that it is not so and that by the application of potentially deadly force they can impose equal economic prosperity upon all. In a sense this is actually correct. What "they" never tell you, however, is that in their model the standard that defines "prosperity" is so low as to invite horror, ridicule, and endless scorn, for that is all their model of a perfect society is able to achieve. It is conceptually similar to them designing aircraft. It has all manner of really cool looking fins and points and what have you, but in the end it never leaves the ground because really cool looking fins and points do not a viable aircraft make. They are as fifth graders attempting to put men on the moon, thinking that the sheer force of will that is be made so will in fact suffice, absent any knowledge of aerospace engineering. In other words, it simply is not going to happen, all wild wishing notwithstanding.
Such people do not in the least way understand humanity. The see it - the sometimes ugly truth - and shrink away as frightened and cowardly toddlers from that which their minds refuse to accept. Positive reality means nothing to them, representing nothing other than a thing to be reviled, from which to recoil, and to be defeated and replaced with their masturbatory fog of perfection. The mode of comportment reminds me of the old R&D cartoon where they start with the "paradigm" on the left, successful completion resides on the right, and in the middle rests a "cloud" with the words therein: "and then a miracle happens". These people have NO idea what they are doing. They only know, at least vaguely, what they want and will stop at nothing to get it, even if they have to impoverish or even murder vast oceans of humanity. What they do not see, likely because they refuse to, is that even if they get everything they want in terms of the steps toward the goal, the objective will never be attained because they cannnot be. The wingless brick will never sustain its own flight. It will always fail the moment third party resources cease to be applied to it. It is inefficient and it fails by necessity.
This, my friends, nutshells the basic problems of the concept of "economic health" as a political notion.
Sorry to have gone on.